Fluid flow meters are well known in the prior art and include a wide variety of designs, including variable area flow meters, impact plate flow meters, float type flow meters and paddlewheel flow meters. Each of these types of flow meters have a distinct metering assembly but no backup system for indicating whether or not fluid is flowing through the meter in the event the metering assembly fails. The lack of a backup flow indicator is particularly a problem in the event a meter jams in a position showing a metered amount of fluid flow when in fact no fluid is flowing through the meter. This can lead to a situation where an operator is unaware that necessary lubricants are not flowing to a machine and the absence of lubricant can eventually cause serious damage to the machine.
One meter known in the prior art has a paddlewheel visible through a window in the meter housing which is operably associated with a metering scale. However, with such a meter it is possible that the paddlewheel could become jammed indicating an absence of fluid flow when in fact fluid is flowing through the meter. Under these circumstances an operator may be forced to shut down a manufacturing process or a machine while fluid supplies are checked although the real problem lies with the meter.
The present application is directed to overcoming one or more of the problems discussed above.